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Structure and Temperature Effects on the Reaction Rate of Aryloxiranes with 3,5-Dinitrobenzoic Acid in Acetonitrile

“…While studying the joint effect of the structure of arenesulfonic acids (YC 6 H 4 SO 3 H) and temperature on the kinetics of oxirane ring opening in 4-nitrophenyloxirane in dioxane, we showed that quantitative estimation of the reactivity in terms of a polylinear regression model (which includes statistically significant cross correlation coefficient ρ YT = -5.8 ± 0.4 [6]) requires that nonadditive effects of factors being varied be taken into consideration. Nonadditive effect of structural factors was found in reactions of X-substituted phenyloxiranes with Y-substituted benzoic acids in acetonitrile at 343 K (ρ XY = -1.1 ± 0.2 [7]). …”

“…An important problem in the chemistry of oxiranes is to reveal quantitative relations holding in opening of the oxirane ring upon variation of internal (structure of the reactants and catalysts) and external factors (reaction medium, temperature).We previously [6,7] made an attempt to simulate the reactivity of the system epoxy substrate-acid reagent by mathematical modeling with the aid of cross correlation analysis of the results of multifactor kinetic experiments. While studying the joint effect of the structure of arenesulfonic acids (YC 6 H 4 SO 3 H) and temperature on the kinetics of oxirane ring opening in 4-nitrophenyloxirane in dioxane, we showed that quantitative estimation of the reactivity in terms of a polylinear regression model (which includes statistically significant cross correlation coefficient ρ YT = -5.8 ± 0.4 [6]) requires that nonadditive effects of factors being varied be taken into consideration.…”

“…The products of these reactions are primary alcohols, 1-aryl-2-hydroxyethyl 3,5-dinitrocarboxylates (Scheme 1) [7]. The kinetic relations holding in the process were studied using more than tenfold excess of the oxirane substrate (S) with respect to 3,5-dinitrobenzoic acid [S] 0 >> [HA] 0 , 0.08-0.17 M, according to the procedure described in [7]. The procedure is based on acid-base titration of the unreacted acid reagent with an aqueous solution of sodium hydroxide.…”

Effect of the structure of carboxylic acids on activation parameters for catalytic acidolysis of epichlorohydrin

“…Epoxide compounds are widely used in drug, pesticide, and polymer chemistry. The interest in oxirane chemistry is due to the unique structure of the ring, which makes it possible to carry out conversions with a very broad range of options when treated with different types of reagents, and epoxide ring opening reactions are considered as model reactions in studying biologically active systems and the complex processes involved in curing epoxy resins [1][2][3][4][5][6][7].A significant number of papers are known to date relating to opening of the oxirane ring when treated with nucleophilic reagents, in particular aliphatic carboxylic acids [2, 3, 7]:It has been established that the reactivity of carboxylic acids in reaction (1) is affected by a number of factors, such as their acidity, their ability to dimerize, the steric accessibility of the nucleophilic center, and temperature [2][3][4][5][6][7]. Note that the reactivity of aliphatic carboxylic acids generally increases compared with acetic acid when either electron-donor or electron-acceptor substituents are introduced [2, 3, 5].…”

“…Epoxide compounds are widely used in drug, pesticide, and polymer chemistry. The interest in oxirane chemistry is due to the unique structure of the ring, which makes it possible to carry out conversions with a very broad range of options when treated with different types of reagents, and epoxide ring opening reactions are considered as model reactions in studying biologically active systems and the complex processes involved in curing epoxy resins [1][2][3][4][5][6][7].…”